WEST VALLEY CITY, Utah (ABC 4 News) – Police say they found no evidence at a campsite as they continue to search for a missing mom.

Susan Powell disappeared from her home Sunday night and hasn’t been seen.

Police now say that her husband Josh Powell is a person of interest and plan to interview him for a third time Friday.

Investigators focused their search Thursday at the Pony Express Trail near Simpson Springs in Tooele County.

“We were looking for evidence that someone went in there and went camping, that’s what we were looking for," said WVC police Captain Tom McLachlan.

Josh Powell told police that he took his two boys, ages 4 and 2, camping late Sunday night. He told police that his wife was sleeping at the home when they left.

According to friends, Powell claims to have left around 12:30 a.m. Monday morning.

Captain McLachlan said they didn’t find any evidence of anyone being at the campsite.

“With the snowstorm everything was pretty well covered over,” he said. “You can’t tell any tire tracks or anything else.”

Captain McLachlan said investigators took cadaver dogs but they could not pick up any scent.

He said that Powell is not considered a suspect at this stage of the investigation.

“We do hope and intent to re-interview him again,” Cpt. McLachlan said.

The police captain did confirm that a Powell’s purse, credit cards and cell phone were among the items taken when they searched the home earlier this week.

And when asked if those are common items left behind by someone who decided to leave he answered this way: “My answer to that is one would usually think those items would be taken but in and of itself does not show a crime,” he said. “This is still a missing person case and our first concern is Susan and locating her, making sure she’s all right.

When asked if she was murdered he said “Like I said, there are many possible solutions to this situation and that’s as far as I’m going to go.”

Meanwhile Powell’s father who lives in a suburb of Seattle spoke with the local ABC affiliate KOMO 4. Chuck Cox offered more details about what police found inside the home.

“They found a wet spot on the floor being dried by two fans,” Cox said. He spoke with Josh Powell Tuesday and said that he offered little insight as to where Susan was.

“I don’t think she’s okay,” he said. “No one has heard from her. Josh and the kids are back and she would not leave her children and she would not leave her purse.

Cox told friends of Susan that he and his wife are headed to Salt Lake City Friday.

A facebook www.facebook.com/topic.php?uid=198478842187&topic=15637#/group.php?v=wall&gid=198478842187 comprised of friends of Susan Powell indicated that a massive search by volunteers is gaining momentum.